Howdy y'all, Came out of work today and truck just cracked and cranked. I lifted the hood and manually engaged the fuel. Solenoid and it started right up. The key would shut it down but not engage it. Does this sound like a solenoid problem or relay....or the fuseable link? I had a similar issue in the past but after a couple of days of manually engaging the solenoid my ignition switch broke inside it and i had to replace it...and it fixed my fuel problem...it just wasn't engaging the power to the relay and the new switch fixed it. But now the switch is only about a year old....it is a NAPA unit and i don't suspect it since it feels solid.

And ideas for me to start narrowing down my search?

Thanks in advance...y'all always give great advise!

JT

 

check the fusable link from the drivers side battery (blue wire into a red/black wire) and make sure its getting a good connection at the battery.. it could also be burnt out.. also the brown wire from the starter is what triggers the pull side of the solenoid so make sure thats clean and getting a good connection at the starter..

i am having problems with mine also, i changed my solenoid, changed the fusable link, new end on the + cable at the battery, etc and mine still occasionally wont start.. they are a hell of a truck

 

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On theses cold mornings...my starter has to be bumped one or two times so it fully engages into the flywheel...is this another symptom...or just a cold starter? The fuseable link "looks" ok...and I replaced the terminal back when I was diagnosing the starting problem when my ignition switch broke. I'll clean up the terminals and check the connection to the starter tomorrow when i can pull it into the garage. AnY tips to rule out the solenoid instead of just replacing it and seeing if the $100 fixes it?

Thanks!

 

Following is from '98 FSM:
"FUEL SHUTDOWN SOLENOID TEST
NOTE: The fuel shutdown (shut-off) solenoid and fuel shutdown solenoid relay are not controlled by the powertrain control module
(PCM).
(1) With the ignition switch off, the solenoid shaft
should be down and the injection pump lever should
be in the shutdown position (no fuel supply to injection
pump) (Fig. 30).
(2) Turn the ignition switch to the CRANK (starter
engage) position and observe the solenoid shaft and
injection pump lever. The shaft should pull up (shaft
retracted into the solenoid) and the pump lever
should be in the run position (fuel being supplied to
injection pump) (Fig. 30).
(3) Release the ignition key from the CRANK to
the ON position. The shaft should remain in the up
position and the pump lever should remain in the
run position (fuel being supplied to injection pump)
(Fig. 30). If the solenoid shaft is not moving, refer to
the following:
(4) Disconnect the solenoid three-wire pigtail wire
harness from the main engine harness.
(5) If the solenoid shaft did not move up when the
ignition switch was in the CRANK position, check for
12 volts at the three-way connector. This will be the
circuit coming from the fuel shutdown solenoid relay.
Refer to Group 8W, for wire connector pin location
and circuit identification. If 12 volts is not present at
this circuit when the key is in the CRANK position,
check the fuel shutdown solenoid relay.
Refer toRelay Test—Fuel Heater/Fuel Shutdown Solenoid in
this section of the group. Also check the wiring
between the relay and the solenoid.
(6) If the solenoid shaft moves up when the ignition
switch is in the CRANK position, but moves
down when the key is released from the CRANK to
the ON position, check the circuit coming from the
ignition switch for 12 volts. Refer to Group 8W, for
wire connector pin location and circuit identification.
(7) If the shutdown solenoid is being replaced, its
shaft length must be adjusted. Refer to Fuel Shutdown
Solenoid Removal/Installation for procedures.

 

See page 6

http://www.genosgarage.com/GenosGara...arageWWWMT.pdf

 

J T, first make sure your solenoid plunger is not full of garbage and making it sticky. The boot rips over time, and road debris gets in.

Take it off and clean it up, new boots are cheap from Foster truck.....

 

WOW! Great Find!!! I also downloaded the TDR buyers guide linked in that article for future reading!


Thanks. So if all the electricals check out that it SHOULD be engaging and its just sticky...I'll see whats involved with cleaning it up with some contact cleaner.

Thanks ya'll I have a punch list of things that should narrow down the problem tonight! (I feel better with this much more than just buying replacement parts and seeing if that fixes it)

 

You have to remove the solenoid to clean it, 5 minute job but the boot is what holds it together.
If the boot is badly torn or missing when you remove the solenoid parts can fly and get lost.
Easy way to prevent this is to turn the key on and lift the solenoid rod up so the coil holds the solenoid together for removal.

 

It was the boot that caused the problem on my 96, after 14 years it melted and gunked up the works. I cut it off, cleaned it up and put on a new one from Geno's for a couple of bucks. Runs like new.

 

Update: truck started right up leaving work today.. BUT didn't this morning and had to manually engage the solenoid?

Anyway since i had planned on it i cleaned all my electrical connections to the batteries. Checked that the fuseable link was intact. Removed the solenoid and it's easy to plunge (except the springs resistance) the boot will need to be replaced but no gunk yet. I checked the voltage while cranking and it had great voltage? So as of now it works and dont know the cause...but if it happens again I'll check the voltage and suspect a relay going out if is intermediately functioning...may even go ahead and have one on hand.


Any input based on what I found today?

Thanks y'all....your such an invaluable resource...wish i could contribute some in return!

 

I've found when the solenoid lift problem is intermittent that it's usually because the fusible link is corroded under the insulation where you can't see it.
Sometimes the high amperage will "weld" the corroded portion back together temporarily and the lift may work for a short while.
Just moving the fusible link wire around a little can make it conduct again also.
If you flex the link back and forth you can usually tell if it's corroded underneath.

Same type of under the insulation corrosion can also occur on the small brown wire at the starter.

 

according to http://www.fostertruck.com/dodge/default.htm It's a 65A fuseable link? What if I just replace it with a regular wire and find a 65A inline fuse? Is there something special with a fuseable link instead of using a replaceable fuse? Seems a fuseable link would would more like to strand you than having a replaceable fuse?

Any thoughts? A few months ago I soldered on a new terminal to the battery so I know corrosion can't get into the terminal but can't say for sure about corrosion under the insulation?

Addition: Cost of terminal and high amp Fuse is more than the $13 for new link from fosters truck in above link.

 

fusible links can handle real short bursts of over the amperage limit where as a regular fuse would just blow.

That being said I know of a few people who have replaced the fusible link with fuses with no ill results

 

What he said, a regular fuse will probably blow every time.
If you can find a slow-blow fuse of that amperage it would work but be pricey.
My local Napa sells the 65 amp links for $7.

 

Several first-gen guys are or have replaced fusible links with fuses. It's on my upgrade list.
https://www.dieseltruckresource.com/...t-t135504.html